The Sex Hormone Binding Globulin (SHBG) test contains 1 test with 1 biomarker.
Brief Description: The Sex Hormone Binding Globulin (SHBG) test measures the levels of SHBG, a protein produced by the liver, in the blood. SHBG binds to sex hormones, such as testosterone and estrogen, and regulates their availability and activity in the body.
Also Known As: SHBG Test, TeBG Test, Testosterone-Estrogen Binding Globulin Test
Collection Method: Blood Draw
Specimen Type: Serum
Test Preparation: Dietary supplements containing biotin may interfere in assays and may skew analyte results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.
Administration of STRENSIQ may interfere in certain assays and may falsely elevate values. For patients receiving STRENSIQ, consideration should be given to using alternate methods.
When is a Sex Hormone Binding Globulin test ordered?
A Sex Hormone Binding Globulin test may be ordered in several situations to assess SHBG levels:
Evaluation of Hormonal Imbalances: If a patient presents with symptoms related to hormonal imbalances, such as abnormal hair growth, irregular menstrual cycles, or infertility, a Sex Hormone Binding Globulin test may be ordered to evaluate SHBG levels and assess hormonal status.
Assessment of Androgen Excess or Deficiency: In individuals with suspected androgen excess or deficiency conditions, such as polycystic ovary syndrome (PCOS) or androgen insensitivity syndrome, the test helps assess SHBG levels and contributes to the overall evaluation of hormonal status.
Monitoring Hormone Replacement Therapy: For individuals receiving hormone replacement therapy, such as testosterone or estrogen replacement, a Sex Hormone Binding Globulin test helps monitor the effectiveness of the therapy and ensure appropriate hormone levels.
What does a Sex Hormone Binding Globulin blood test check for?
SHBG is a liver-produced protein that strongly binds to the hormones testosterone, dihydrotestosterone, and estradiol. SHBG distributes these hormones in the blood as physiologically inactive versions when they are bound. This test examines the amount of SHBG in the blood and is most commonly used to determine whether a person has too much or too little testosterone.
In men, SHBG binds roughly 45 percent to 65 percent of testosterone in the blood, with the rest weakly and reversibly linked to albumin. Only around 2% to 3% of testosterone is accessible to tissues as free testosterone, but testosterone that is weakly linked to albumin is also bioavailable and can be rapidly absorbed by the body's tissues.
In women, a somewhat higher percentage of testosterone is bound to SHBG in the blood than in men. SHBG is important in controlling the quantities of bioavailable male sex hormones and estrogens circulating throughout the body in women. Because SHBG has a stronger affinity for the androgens testosterone and DHT, women with low SHBG may experience signs and symptoms of androgen excess.
A total testosterone test does not differentiate between bound and unbound testosterone; instead, it determines the total amount of testosterone present. In many circumstances, this is sufficient to determine if testosterone production is excessive or inadequate. However, if a person's SHBG level is abnormal, the total testosterone level may not accurately reflect the amount of testosterone available to the person's tissues. When a person's indications and symptoms do not match the results of a total testosterone test, a SHBG test may be conducted.
Lab tests often ordered with a Sex Hormone Binding Globulin test:
Measuring SHBG can help evaluate the status of a person's sex hormones, especially when issues related to hormone balance are suspected. Here are some tests that are commonly ordered alongside SHBG and the reasons why:
- Purpose: To measure the levels of testosterone in the blood, which can be affected by the amount of SHBG.
- Why Is It Ordered: If SHBG levels are abnormal, it can alter the amount of free (biologically active) testosterone. Total and free testosterone levels are often assessed in conjunction with SHBG to evaluate conditions such as hypogonadism, infertility, or polycystic ovary syndrome (PCOS).
- Purpose: To measure the levels of estradiol, a form of estrogen that can also bind to SHBG.
- Why Is It Ordered: Similar to testosterone, it is important to measure estradiol levels to evaluate how SHBG may be affecting the overall hormonal balance, especially in the evaluation of menstrual irregularities or menopause.
Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH):
- Purpose: To evaluate the hormones that stimulate the gonads (ovaries in women and testes in men).
- Why Is It Ordered: FSH and LH levels can help determine the cause of low sex hormone levels and assess ovarian or testicular function.
Complete Blood Count (CBC):
- Purpose: To provide a broad picture of blood health.
- Why Is It Ordered: Though not directly related to SHBG levels, a CBC can help identify health issues that might indirectly affect hormone levels, such as liver dysfunction.
Liver Function Tests:
- Purpose: To assess liver health, which produces SHBG.
- Why Is It Ordered: Since the liver produces SHBG, liver health can directly impact SHBG levels, and therefore the bioavailability of sex hormones.
- Purpose: To measure levels of prolactin, a hormone that can affect the body's hormonal balance.
- Why Is It Ordered: Elevated prolactin can lead to decreased estrogen or testosterone levels and may be associated with conditions affecting SHBG levels.
- Purpose: To measure the levels of DHT, a potent androgen derived from testosterone.
- Why Is It Ordered: DHT levels can be relevant in conditions like hair loss (androgenic alopecia) and can be affected by SHBG levels.
Insulin and Glucose Tests:
- Purpose: To measure blood sugar levels and insulin resistance.
- Why Is It Ordered: Insulin resistance can affect SHBG levels, particularly in women with PCOS.
Dehydroepiandrosterone Sulfate (DHEA-S):
- Purpose: To measure levels of DHEA-S, an androgen precursor produced by the adrenal glands.
- Why Is It Ordered: DHEA-S can contribute to the body's overall androgen status and may be evaluated in the workup of hirsutism or virilization.
Thyroid Function Tests:
- Purpose: To assess thyroid health, which can influence SHBG levels.
- Why Is It Ordered: Both hyperthyroidism and hypothyroidism can affect SHBG levels, altering sex hormone bioavailability.
These tests, when ordered alongside SHBG, can help evaluate disorders related to hormone balance and metabolism, such as PCOS, erectile dysfunction, menstrual irregularities, and suspected endocrine syndromes. They can also provide insight into how other physiological conditions might be influencing sex hormone levels. The specific tests selected will depend on the patient's symptoms, sex, and medical history.
Conditions where a Sex Hormone Binding Globulin test is recommended:
A Sex Hormone Binding Globulin test is commonly ordered for:
Polycystic Ovary Syndrome (PCOS): PCOS is a condition characterized by hormonal imbalances, including elevated levels of androgens. A Sex Hormone Binding Globulin test helps assess SHBG levels and contributes to the diagnosis and management of PCOS.
Hypogonadism: Hypogonadism refers to decreased sex hormone production, which can manifest as testosterone or estrogen deficiency. A Sex Hormone Binding Globulin test aids in the evaluation of hypogonadism and helps determine appropriate treatment interventions.
Estrogen-Related Disorders: Conditions related to estrogen imbalances, such as estrogen excess or deficiency, may require a Sex Hormone Binding Globulin test to evaluate SHBG levels and assess overall hormonal status.
How does my healthcare provider use a Sex Hormone Binding Globulin test?
Healthcare providers use the results of a Sex Hormone Binding Globulin test to:
Evaluate Hormonal Imbalances: Abnormal SHBG levels can indicate hormonal imbalances, such as androgen excess or deficiency, or estrogen-related disorders. The Sex Hormone Binding Globulin test aids in the diagnosis and monitoring of these conditions.
Guide Treatment Decisions: Based on the Sex Hormone Binding Globulin test results, healthcare providers can determine the appropriate treatment plan, such as hormone replacement therapy or interventions to address underlying hormonal imbalances.
Monitor Hormone Replacement Therapy: For individuals receiving hormone replacement therapy, the Sex Hormone Binding Globulin test helps monitor the effectiveness of the treatment and ensure appropriate hormone levels are achieved.
By effectively utilizing the results of a Sex Hormone Binding Globulin test, healthcare providers can evaluate hormonal imbalances, guide treatment decisions, monitor hormone replacement therapy, and make informed decisions regarding patient care and interventions related to sex hormone regulation.
Most Common Questions About the Sex Hormone Binding Globulin test:
Understanding the Test
What is the Sex Hormone Binding Globulin (SHBG) test?
The SHBG test is a blood test that measures the level of Sex Hormone Binding Globulin in your blood. SHBG is a protein produced by the liver that binds to three sex hormones found in both men and women: estrogen, dihydrotestosterone (DHT), and testosterone.
What does the Sex Hormone Binding Globulin test reveal about my health?
SHBG levels can affect the amount of testosterone that is available for the body to use. Higher SHBG levels mean that less free testosterone is available, which can cause symptoms of low testosterone. On the other hand, lower SHBG levels mean that more testosterone is available, which can lead to symptoms of high testosterone.
Interpreting the Results
What does a high SHBG level mean in the Sex Hormone Binding Globulin test?
A high SHBG level can mean that there's less free testosterone or estrogen available for the body to use. This can be caused by several conditions, including liver disease, hyperthyroidism, and eating disorders.
What does a low SHBG level mean in the Sex Hormone Binding Globulin test?
A low SHBG level means that more testosterone or estrogen is available for the body to use. This can occur due to conditions like hypothyroidism, obesity, polycystic ovary syndrome (PCOS), and type 2 diabetes.
The Test in Different Situations
How is the Sex Hormone Binding Globulin test used in the context of diagnosing PCOS?
In the case of PCOS, the SHBG test can help doctors understand hormonal imbalances better. Women with PCOS tend to have lower SHBG levels, which can contribute to high levels of free androgens, including testosterone, leading to symptoms such as irregular periods, excess hair growth, and acne.
How might the Sex Hormone Binding Globulin test be used in assessing men's health?
In men, the SHBG test can help diagnose conditions related to low or high testosterone, such as hypogonadism, infertility, or testosterone resistance. It can also be used in cases of suspected androgen disorders.
What role does the Sex Hormone Binding Globulin test play in hormone replacement therapy (HRT)?
The SHBG test can be used to monitor and adjust hormone replacement therapy, especially in transgender healthcare. It helps in assessing the free levels of hormones available for use by the body, guiding the adjustments in dosage of administered hormones.
About the Test
Can certain medications affect the results of the Sex Hormone Binding Globulin test?
Yes, certain medications can affect the results of the SHBG test. For example, hormone replacement therapy, antithyroid medications, oral contraceptives, and certain antifungal medications can increase SHBG levels.
What factors can influence the results of the Sex Hormone Binding Globulin test?
Factors that can influence SHBG levels include age, sex, liver function, body mass index, certain medications, and hormonal fluctuations.
Understanding the Implications
How does the Sex Hormone Binding Globulin test contribute to understanding my fertility issues? As SHBG regulates the amount of active sex hormones in the body, imbalances in SHBG levels can impact fertility. For example, low SHBG levels can lead to an excess of free testosterone, which can interfere with ovulation in women and sperm production in men.
What happens if the results of my Sex Hormone Binding Globulin test are not normal?
Abnormal SHBG levels can indicate various conditions depending on whether they're high or low. For instance, high levels can be linked to liver disease or hyperthyroidism, while low levels can be related to PCOS or hypothyroidism. Treatment will depend on the underlying cause.
Risks and Precautions
Are there risks associated with having high or low SHBG levels in the Sex Hormone Binding Globulin test?
Yes, both high and low levels of SHBG can be associated with health risks. High SHBG levels can cause symptoms of low testosterone or estrogen, while low SHBG levels can lead to symptoms of excess testosterone or estrogen. These imbalances can impact various systems in the body.
Can pregnancy affect the results of the Sex Hormone Binding Globulin test?
Yes, pregnancy can affect SHBG levels. During pregnancy, SHBG levels tend to increase due to elevated levels of estrogen, leading to higher total but normal free levels of sex hormones.
What should I do if I have a family history of hormone-related disorders and abnormal SHBG levels?
If you have a family history of hormone-related disorders, it might be advisable to discuss this with your healthcare provider. They may recommend regular screening tests, including SHBG tests, to monitor hormone levels and detect any potential imbalances early.
Can the Sex Hormone Binding Globulin test provide insights into my risk of developing certain cancers?
Potentially. Some research suggests that low SHBG levels may be associated with an increased risk of certain cancers, suchas breast cancer or ovarian cancer in women and prostate cancer in men. However, more research is needed in this area, and the SHBG test should not be used as a standalone diagnostic tool for cancer.
Can the Sex Hormone Binding Globulin test indicate metabolic syndrome?
Yes, research suggests that low levels of SHBG could be associated with an increased risk of metabolic syndrome, a cluster of conditions including high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels. Therefore, the SHBG test could potentially provide insights into an individual's risk of developing metabolic syndrome.
Dealing with Abnormal Results
How can I increase my SHBG levels if they are low according to the Sex Hormone Binding Globulin test?
Your healthcare provider might recommend lifestyle changes like maintaining a healthy weight, regular physical activity, and a balanced diet. They may also adjust any medications that could be affecting your SHBG levels. In some cases, specific treatment might be needed to address the underlying condition causing the low SHBG levels.
How can I decrease my SHBG levels if they are high according to the Sex Hormone Binding Globulin test?
If your SHBG levels are high, treating the underlying condition causing this increase is important. This might involve adjusting your medication if it's contributing to high SHBG levels, or treating conditions like liver disease or hyperthyroidism.
Interpreting the Test Results
How are the results of the Sex Hormone Binding Globulin test interpreted?
The results of the SHBG test are typically reported as a numerical value and compared with reference ranges. These reference ranges can vary depending on the lab and individual factors like age, sex, and overall health. Therefore, it's important that your healthcare provider interprets your results.
Can I interpret the results of my Sex Hormone Binding Globulin test on my own?
While you can understand the basic implications of high or low SHBG levels, interpreting the exact results and their significance should be done by a healthcare provider. They can consider your overall health, symptoms, and other test results to provide an accurate interpretation.
What additional tests may be needed along with the Sex Hormone Binding Globulin test?
Your doctor might also recommend tests for testosterone, estrogen, and other hormones to give a complete picture of your hormonal health. If liver disease is suspected, liver function tests might also be needed.
The Test in Relation to Other Conditions
What is the relationship between the Sex Hormone Binding Globulin test and diabetes?
Lower levels of SHBG have been associated with an increased risk of type 2 diabetes. SHBG might play a role in glucose metabolism, and lower levels could potentially contribute to insulin resistance, a key feature of type 2 diabetes.
Can the Sex Hormone Binding Globulin test be used to monitor treatment for hormonal disorders?
Yes, the SHBG test can be used to monitor treatment for hormonal disorders. Changes in SHBG levels can indicate how well the body is responding to treatment.
What role does the Sex Hormone Binding Globulin test play in understanding conditions related to aging?
SHBG levels can naturally change with age. In men, SHBG levels typically increase with age, which can lead to a decrease in free testosterone levels. This can contribute to symptoms associated with "low T" or late-onset hypogonadism. In women, SHBG levels can fluctuate with menopausal changes.
Can the results of the Sex Hormone Binding Globulin test help in the diagnosis of thyroid disorders?
Yes, since SHBG levels can be influenced by thyroid hormones, abnormal SHBG levels could potentially indicate a thyroid disorder. For instance, high SHBG levels could suggest hyperthyroidism, while low levels might suggest hypothyroidism. However, other tests like TSH, T3, and T4 are needed to confirm a diagnosis of thyroid disorder.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results